1. Field of the Invention
The present invention relates generally to material handling and land vehicles. In particular, the present invention relates to a wheeled vehicle equipped with a bale handling system for retrieving, transporting, and stacking hay bales.
2. Description of the Related Art
Conventional methods of harvesting hay for livestock feed involve cutting the hay, baling the hay, removing the baled hay from fields, and storing the baled hay in stacks. To obtain the maximum production from a field of hay, it is important that all of these harvesting steps are performed in a timely and efficient manner.
A number of machines have been developed for retrieving, transporting and stacking hay bales. For example, U.S. Pat. No. 5,320,472 issued to Matlack et al. discloses a bale loading and transporting vehicle that can be used to load, transport and unload large rectangular or round bales from a hay field. The hay bales are loaded onto the vehicle by a front bale loader that raises the bales from the field and places them at the highest part of an inclined platform that slopes from the front of the vehicle to the rear. The bales are then discharged from the rear by pivoting a rear bale gate to a lower discharge position and allowing the bales to slide from the rear end of the inclined platform.
U.S. Pat. No. 4,952,111 issued to Callhan and U.S. Pat. No. 4,971,504 issued to Klompien both disclose devices for picking up and stacking large hay bales. These devices both include pickup forks at the front end of a vehicle for placing the bales on a stacking bed. Once the stacking bed is full, it can be pivoted to a vertical position for stacking the bales.
U.S. Pat. No. 7,090,456 issued to Ost et al. discloses a hay bale stacker having front pickup forks that lift the bales at the front of the vehicle, raise the bales over the cab of the vehicle, and place the bales on a platform that slopes downwardly toward the rear of the vehicle. The bales are rotated approximately 90 degrees as they are lifted and placed on the vehicle platform. A catch means for the bales is provided to control the bale's movement down the sloped bed as the bales are loaded. The platform can be tilted to a near vertical position to stack the loaded bales on the ground.
The bale handling vehicles described above are presumably suitable for their intended purposes. However, these bale handling vehicles have a limited capacity because the sloped platform creates a high center of gravity when fully loaded with hay bales, which can make the vehicle unstable as it moves across a field. The bale handling vehicles are also limited in their unloading options.